Search results for "FLUID"
showing 10 items of 5513 documents
Scientific evidence on the usefulness of intraarticular hyaluronic acid injection in the management of temporomandibular dysfunction
2010
Abstract Hyaluronic acid (HA) is found in high concentrations in cartilage and synovial fluid, and is an important component of the extracellular matrixes ? exerting joint lubrication and buffering actions thanks to its viscoelastic properties. The present study examines the scientific evidence found in the current literature on the usefulness of the intraarticular injection of HA in patients with temporomandibular dysfunction. A literature search was made up until May 2008 in the following databases: PubMed / MEDLINE. Of the articles found in the literature, the present review included 18 relevant studies on the application of HA in the temporomandibular joint (TMJ). The quality, level of …
The influence of the decompressive operation on the intracranial pressure and the pressure-volume relation in patients with severe head injuries.
1978
Measurements of intracranial pressure by ventricular catheter were performed in 47 patients with severe head injuries. Thirty-three patients with decompressive operations such as osteoclastic craniotomy and dilatation by means of duraplastic have been compared with 14 patients with closed heads with regard to volume pressure response (intracranial elasticity). This was determined either by intraventricular injection of 2 ml saline or by drainage of cerebrospinal fluid. The examination clearly shows that patients with closed heads have a much higher intracranial elasticity than patients who have decompressive operations, so that in the first group minor differences of the intracranial volume…
Evaluation of efficacy and biocompatibility of a new absorbable synthetic substitute as a dural onlay graft in a large animal model.
2016
Numerous dura substitutes are commercially available, but no absorbable synthetic dura repair product has been used for both onlay and suture applications.The safety and effectiveness of a new absorbable synthetic substitute composed of Poly-L-lactide microfibers as onlay dural graft were evaluated.Physical properties and performance of the microfibrous synthetic dural substitute implanted as an onlay or suturable grafts were compared with these commercial products, including CODMAN ETHISORB™ Dura Patch and DuraGen™ Dural Graft Matrix, in a canine duraplasty model. The cerebrospinal fluid (CSF) leakage, macroscopic and microscopic observation at 30 and 90 days after implantation were invest…
Coronary Stent Strut Fractures: Classification, Prevalence and Clinical Associations
2021
Introduction. The frequency, characteristics and clinical implications of Strut fractures (SFs) remain incompletely understood. Methods and results. A total of 185 (160 patients) newer-generation drug-eluting stents (DES) were imaged. SFs were found in 21 DES (11.4%) and were classified in four patterns: one single stacked strut (41%)
Numerical resistive relativistic magnetohydrodynamics
2018
La presente tesis se desarrollada dentro del marco de la Magnetohidrodinámica Resistiva Relativistica (RRMHD; por sus siglas en inglés) y uno de sus principales objetivos es el caracterizar las condiciones físicas que optimizan la disipación de campos magnéticos en plasmas relativistas, especialmente en aquellos que son de interés astrofísico. Para alcanzar este objetivo, realizamos el estudio de los denominados modos de ruptura dobles, bajo condiciones ideales (IDTMs; por sus siglas en inglés) que maximizan sus tasas de crecimiento. Se demuestra que en el régimen relativista los IDTMs pueden crecer en escalas de tiempo de unos pocos tiempos característicos de Alfvén, desarrollando regímene…
La combustione HCCI mediante miscele di gas naturale e benzina: una prima esperienza sperimentale
2016
Si presentano in questo articolo i risultati di una sperimentazione volta a valutare la possibilità di effettuare una combustione HCCI (Homogeneous Charge Compression Ignition) stabile mediante l’impiego di miscele di gas naturale (GN) e benzina. La combustione HCCI ha ottime prerogative di basso impatto ambientale, ma la sua realizzazione pone qualche problema di stabilità al variare delle condizioni di carico richieste al motore: lo studio condotto mostra come l’impiego di miscele di GN e benzina, la cui composizione permette di variarne la resistenza all’autoaccensione, consente di ampliare il campo di funzionamento stabile della combustione HCCI. In the last decade the HCCI combustion h…
A New Simple Function for Combustion and Cyclic Variation Modeling in Supercharged Spark Ignition Engines
2022
Research in the field of Internal Combustion (IC) engines focuses on the drastic reduction of both pollutant and greenhouse gas emissions. A promising alternative to gasoline and diesel fuel is represented by the use of gaseous fuels, above all green hydrogen but also Natural Gas (NG). In previous works, the authors investigated the performance, efficiency, and emissions of a supercharged Spark Ignition (SI) engine fueled with mixtures of gasoline and natural gas; a detailed research involving the combustion process of this kind of fuel mixture has been previously performed and a lot of experimental data have been collected. Combustion modeling is a fundamental tool in the design and optimi…
Fabrication techniques for developing a functional microfluidic glass device suitable for detection in optical spectroscopy system
2012
Microfluidic devices offer the chance to manipulate and analyze fluids including bioassays and chemical reactions. In this study, a method to develop a microfluidic analysis system is proposed for detection of nanotubes by a Raman acquisition setup. Microchannels where fabricated in sodalime glass substrate by MeV ion beam lithography or electron beam lithography and wet etching. Fusion bonding (550 °C) was used to seal the microchannels. As a result a prototype microfluidic device with 1.6 µm deep channel that exhibit efficient sealing and suitable channel geometry was obtained. The microfluidic device was tested in a Raman spectroscopy detection system and the collected spectra showed the…
Fluid flow in porous media with the lattice-Boltzmann method
2005
Noise effect in a FitzHugh-Nagumo circuit driven by a bichromatic signal
2013
We analyze the response of a nonlinear circuit exactly ruled by the FitzHugh-Nagumo equations. This circuit is submitted to a bichromatic signal including a high frequency and a low frequency. In absence of noise, we show that for an appropriate amplitude of the high frequency driving, the response of the circuit estimated at the low frequency can be optimized via the phenomenon of vibrational resonance. Next, we show that under certain conditions, noise can contribute to the effect of vibrational resonance. Colored noise is also considered. Our experimental results are confirmed by a numerical analysis.